Routing Algorithms In AMR Systems Based On Power Line Communication

In recent years, the technology of low-voltage power line as communication media transmitting data has been studied intensively and got wide application in projects such as auto meter reading(AMR) systems, intelligent buildings, and street light control systems. Being a channel originally designed for transmitting energy instead of messages, the power line is of course not a very good media for communication. The radical change of power line channel makes network of electrical nodes become every unreliable, this has been a problem of power line carrier communication in engineering applications. So, the study of automatic routing becomes hot and critical spot in low narrow-band carrier communication technology.The paper studies physical characteristics of low-voltage carrier communication firstly, which includes: powerline impedance characteristics, attenuation characteristics and network noise characteristics, then analyses routing algorithm and its limitations in power line carrier communication.Basis on this, the thesis begins with logical structure and characteristics of power line carrier communication. The low-voltage power line carrier automatic meter reading systems need a routing algorithm to find a reasonable path for data transmission, to achieve upon request and data collection applications. According to the characteristics of low-voltage power line,this paper introduces 3 routing algorithms for two application problems in automatic meter reading systems. They are Single-Path Routing(SPR) algorithm and All -Path Routing(APR) algorithm for the upon request application. And Parallel Routing Algorithm(PRA) for the data collection application.The path to each node is determined by the concentrator in SPR algorithm. If the concentrator could find the shortest path, SPR algorithm would match the theoretical lower bound in time and energy. APR algorithm is close to the theoretical lower bound of time. APR algorithm which has high meter reading success rate can run without routing knowledge. It is the strongest algorithm to overcome the time-varying and random interference in all of three algorithms. PRA algorithm which uses temporary routing knowledge and transport packets parallelly could reduce the number of packets to reduce time consuming in meter reading task. PRA algorithm also has a multi-task mechanism. This paper also designs and implements routing information management program for local and global routing information. There are three tables Adjacent Node Table, Upward Destination Table and Upward Routing Table in local routing information management program. The Node Table and Adjacency Table consist of global routing information management program.The algorithms introduced here have been implemented in SSC1630 and SSC1640 PLC chips by Qingdao Eastsoft Company. It can be shown that the algorithm can improve the meter reading success rate in AMR systems.